This invention relates to the field of embossing machines, and is preferably used in connection with the type of embossing equipment illustrated in the U.S. patent to Bolten et al, U.S. Pat. No. 4,091,910. Since the introduction of equipment in accordance with the Bolton patent, various changes and improvements have been made to render the machine more automatic in operation and particularly to carry out the storing of blank cards or plates in a hopper, feeding them from the hopper to the embossing location, and from there to a receiver so that the entire procedure can proceed with minimum operator intervention. This equipment, known as the AM Addressograph E300 Embosser, involved first the use of a frame system arranged centrally of the machine to position a plate during embossing so that the characters are embossed in sequence on the proper line and at the proper positions along the line. The frame system was made up of an inner frame having parallel rails with grooves forming a movable track segment in which the upper and lower edges of the plate could be slidably received. This inner frame also carried means for trapping and registering the plate at a predetermined location along the movable track segment in response to its being slid into the movable track segment from the input end. The inner frame was vertically shiftable on guides carried by the outer frame, which in turn was horizontally shiftable on fixed guides running parallel to the character lines on the embossed plate. Both frames were arranged to be positioned along their guides by electrically controlled mechanism, including cables and stepping motors, in such manner as to place the plate in proper position for embossing each character thereon. The drive system for the horizontally shiftable frame had two modes of operation, one a step by step locating mode for sequential character embossing, and the other an extended travel mode for allowing the inner frame tracks to receive or discharge plates.
At the input end of the machine there was a hopper for holding a stack of unembossed plates and advancing them stackwise to a picking position, and fixed upper and lower rails forming a fixed track segment for receiving a plate picked from the stack and guiding it into the machine.
At the output end the arrangement was somewhat similar in that there was provided a fixed exit track segment and a receding stack receiver for accepting and holding the embossed plates in stacked relationship. Horizontally oscillating cursors were also provided for driving picker and pusher elements to withdraw a blank plate from the hopper and step it along through the track, finally moving an embossed plate into the receiver. These were driven in proper timed relationship by a cable system and electric motors.
The operating sequence of this mechanism called for the horizontally shiftable frame to move the track segment of the inner or vertically moving frame into close register with the fixed track segment at the input end. Then the picker slider would be activated to draw a fresh plate from the hopper stack through the input fixed track segment and to move a waiting plate onto the movable track segment where it would be trapped or latched in place. Thereafter the horizontally movable frame would carry the plate to a central location between the embossing punches and dies where the motions required during the embossing operation would be carried out by the drives for the vertically and horizontally movable frames. Upon completion of embossing, the vertically moving frame would be restored to the datum position and the horizontally moving frame would be shifted by its drive until the movable track segment on the vertically moving frame was in close register with the end of the fixed track segment on the output end, whereupon pusher elements would be activated to move the embossed plate to the fixed track segment and place another waiting card on the face of the stack in the receiving stacker.
The correct positioning of the plate on the movable track section was controlled by an inlet trapping member which normally blocked the track but could be swung aside by the incoming plate as it arrived. The trapping member was hinged to swing about a horizontal axis adjacent the upper rail, and spring pressed to return after the plate had passed. At a location about one plate length from the inlet trapping member was a retention member also positioned to block the track, hinged on a horizontal axis on the upper rail and spring urged both into blocking position and in a direction towards the plate along its hinge axis to serve as a return device to bring the plate back to its initial position after each embossment. This retention device was releasable only when the frame system was moved to release position adjacent the output track, at which time a fixed cam would displace the retention member laterally off the track to allow the pusher to move the plate onto the fixed output track segment. Because of their nature, the trapping means and the retention means would lie within the sweep of the rotary embossing heads if they were to occupy the same plane. Accordingly embossment of a narrow margin along the upper edge of a plate could not have been performed if required for any reason.
The equipment just described has operated very effectively and has given good service in usual embossing situations. Recently, however, applications have arisen in which there has been a requirement for embossing machines which can be made to accept plates of varying sizes and shapes. At the present time these applications relate primarily to automobile manufacture, but other needs for this capability undoubtedly exist. In situations where the need for embossed workpieces represents a rather low volume in comparison with such commonly embossed items as credit cards and the like, and where there are various types, sizes and shapes of plates which must be embossed, it is difficult to justify the cost of a number of highly automated embossers such as would be needed to handle several individual plate configurations. However, it has been determined that if there are a sufficiently large number of machines required at different locations it could be economically feasible to purchase or lease the machines, provided that each machine could be made to accommodate all of the various plate configurations in use by the customer, at least to the degree that a service man or a well trained operator could, with the substitution of a few readily accessible minor parts and some minor adjustment, effect a quick but fully operative conversion of the machine. No such machine has existed heretofore and customers with this particular type of requirement have had to be content with the inconveniences of embossers each designed to handle one particular configuration of workpiece with no possibility of switching from one machine to another for a particular plate configuration without undertaking a substantial rebuilding of the machine.